The Xiris Blog

High Voltage Cable is a multi-layer cable used for running high voltages underground or underwater. The integrity of the cable is very important – the insulation of the cable must not deteriorate due to the high voltage power being transmitted.

Often a high-voltage cable will have a metallic shield layered over the insulation, connected to the ground and designed to equalize the dielectric stress on the insulation layer. This metallic shield is effectively a welded tube, wrapped around the conducting cores and insulating layers of the cable and welded together as the cable is made.

Various High Voltage Cable Samples(courtesy: KEI Industries)

If the fabrication process of forming and welding the metal sheath tube is not done properly, the cable may fail its final quality specification and may require to be destroyed, a very costly prospect for the manufacturer. Using a weld inspection system such as the WI2000 system from Xiris, measurements can be made on the production line of the final welded sheath of various attributes such as Mismatch, weld Bead Height and Freezeline to help determine if the metal sheath tube is being welded correctly.

If any of those measurements begin to drift out of tolerance, an operator can be alerted to make adjustments in the input parameters to bring the process back in control avoiding any scrap production. The result is a better quality welded sheath tube on the cable that has a better chance of meeting the final end user’s specifications.

Who doesn’t love an inspiring transformation story? Weld inspection systems truly are capable of transforming your quality assurance processes and one of our Spanish customers has quite the story to prove it.

Tubos de Legutiano Automoción (TLA) is a manufacturer of high-quality tubular products for the automotive market. By producing thin-walled exhaust pipes, TLA helps their customers reduce the weight of their parts, while maintaining high quality standards that are able to withstand the strict demands of the automotive industry.

TLA recently said that their most important customer, a large automotive parts supplier based in France, was both surprised and delighted to notice a sudden, significant improvement in TLA’s quality, so much so that they wanted to pay them a visit.

Once visiting TLA, the French automotive parts supplier realized that the improvement in quality was due to the introduction and implementation of the Xiris WI2000Weld Inspection system used on their two tube lines. By detecting defects that were previously not detectable using any other NDT test process, TLA was able to address the imperfections that were plaguing their production for years.

The management of TLA commended Xiris’ systems saying:

“Without precision tools that allow us to move forward and work under this precept, it would be difficult to be able to develop products according to the new demands. That is why the Xiris WI2000 has been the key for increasing the quality of our company, reducing set-up times, monitoring the quality of the product in real time and allowing to interact with accurate information in the production process.”

The result was that, once implemented, the WI2000 systems were able to catch defects and help perform better process monitoring to keep their tube product in control. Consequently, fewer defects made their way to the end of the production line and shipped to their customer in France.

Xiris’ High Dynamic Range (HDR) welding cameras can be used in a multitude of ways, some of which our customers have discovered on their own.

For example, a manufacturer of thick-walled steel pipe recently figured out how to use our cameras in a way that has greatly improved the efficiency of their coil joining process.

Operators only have about 10 minutes to end-sheer, mate, and weld coils during the semi-automatic front-end part of the process. The cost of coil joint failure is high, so the manufacturer would stop the tube mill to check on the integrity of the coil joint before continuing.

Even though the stoppage prevented more-costly failures, it had its own cost. What our customer needed was a way to adequately monitor the end joining in the infeed buffer of the pipe mill without having to stop the process to assure correct coil matching.

They knew the capabilities of our cameras to enable real-time remote monitoring of weld processes with greater visibility than ever before possible. So they developed a plan to use Xiris XVC-110e50 cameras to monitor the coil joining during the front end of the process. This monitoring eliminates the need for routine stoppages.

This solution also keeps operators safer. Coil joining is performed using a MIG welding torch mounted onto a linear track with dual-axis torch position. Previously, operators had to be close enough to the torch to see what was happening with the weld. With the Xiris HDR cameras, they have a clear view of the coil joining process from a safe remote location.

With their creative use of our HDR camera technology, this manufacturer was able to significantly reduce the time and cost of coil joining, while increasing consistency.

During tube production, immediately after the tube has been welded and before any further in-line processing is done, the weld bead must be scarfed off the tube. Scarfing is the process whereby the weld bead is cut off with a knife, or scarfing tool. Unfortunately, if the scarfing tool is not done properly, the tube may not meet end user customer specifications because of a rough surface left behind by the scarf tool. The result can be the primary contributor to creating a leak path on a compression fitting.

Using a surface profiling tool such as the Xiris WI2000, the scarf defect measurement can be used to detect how well the scarfing tool is cutting the weld bead and indicate the amount of scarf tool wear.

Scarf tool wear describes the gradual failure condition of a scarf cutting tool on a tube mill as a result of ongoing use. It can occur either as flank wear in which the portion of the scarf tool in contact with the welded tube erodes over time sometimes causing a ridge to be left behind in the scarf zone; or as crater wear, in which contact with chips of weld bead erodes the rake face of the tool causing an uneven cut surface; or a cluster of weld bead material building up on the face of the tool causing it to dredge a groove in the scarf zone. These conditions are somewhat normal for tool wear, and they do not seriously degrade the use of the scarf tool until it becomes serious enough to cause a scarf tool cutting edge failure that may be a concern for a potential leak path for the tube in its final use.

The scarf defect measurement on the WI2000 looks for any significant deviations in surface height above or below the ideal scarf surface. The Scarf Defect will detect the absolute value of the largest defect on the scarf surface. Any significant amount of scarf tool wear could reduce the specifications and performance of the final tube, especially for some automotive applications where tight assembly requirements or a smooth, scratch free surface is required.

The Definition of a Scarf Tool Wear: The scarf plane can be defined as the straight line drawn between the left and right scarf edges. Any detected features above or below the scarf plane, are measured as a scarf defect. The actual amount of wear is defined as the distance from the scarf plane measured perpendicularly to the scarf plane.

Lighter wall mild steel pipe production requires bead height monitoring for bead ripple. Bead ripple is a condition sometimes associated with a weld process that is too hot and may result in longitudinal weld cracks. Bead ripples appear along the length of the weld bead as undulations with measurable differences in height by as much as 1/8” (3 mm). Often the height of the bead ripple on a welded pipe is a function of the heat that has gone into the weld process: the higher the heat, the greater the height of the bead ripple. In most applications, a weld bead should have a smooth, consistent height as an indicator of a stable weld process.

An image of a weld bead with bead ripple

In some applications, a weld bead ripple can be desired, such as in certain coated steel products. This ensures that all contaminants from the area of the weld have been squeezed out, preventing potential inclusions from occurring in the weld bead, which would result in compromised weld quality.

By measuring the bead height on a weld bead over a period of time using a laser based triangulation system , an indication of the smoothness of the weld bead can be made. By calculating ongoing historical statistics of the head height (e.g. min/max, average, standard deviation), an indication of smoothness of the weld bead or bead ripple can be made. Tolerances of the amount of smoothness or ripple can be set to match the process and when exceeded, an alarm can be set.

Measuring the weld bead height over successive images can detect bead ripple over time

Xiris' WeldInspection System Helps Identify the Root Cause of Variations in Tube Production

Many applications require tube producers to identify and document their tubes by batch, date and sometimes even time stamp for trace-ability. If a tube segment fails at a sub process or worse at the end user, a detailed analysis and root cause investigation follows.

Audit Log Files from Xiris' WeldInspection System

When the original tube production date and time information is available, a helpful tool to identify anomalies is to review the audit log files generated onXiris’ WeldInspection system.The audit log files are date and time stamped and easily accessible to look for any weld related geometries that may have deviated for a time period during the production run.

Variations may be a change in bead shape/size that can be an indicator of squeeze pressure or weld heat change. With the WeldInspection system monitoring multiple geometrical conditions such as mismatch, bead height, width and potential freeze line, much information can be gained by reviewing the log files and identifying a potential root cause. Additionally if a particular condition has been identified as the potential cause, the audit logs can be utilized to determine for how long that condition existed therefore helping reduce the volume of product that might be quarantined for further evaluation.

If you are interested in learning more about how our WeldInspection system can benefit you and your company, please contact us here.